1,2,4,5-Tetra­methyl-3,6-diphenyl-1,2,4,5-tetra­aza-3,6-diphosphinane

Kriel, F.H.; Caddy, J.; Fernandes, M.A.

doi:10.1107/S160053680800665X

organic compounds

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ISSN: 2056-9890

Volume 64| Part 4| April 2008| Page o708

doi:10.1107/S160053680800665X

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1,2,4,5-Tetramethyl-3,6-diphenyl-1,2,4,5-tetraaza-3,6-diphosphinane

Frederik H. Kriel,^a ^* Judy Caddy ^a and Manuel A. Fernandes ^b

^aProject AuTEK, Mintek, Private Bag X3015, Randburg 2125, South Africa, and ^bMolecular Science Institute, School of Chemistry, University of the Witwatersrand, PO Wits, 2050 Johannesburg, South Africa
^*Correspondence e-mail: erikk@mintek.co.za

(Received 25 February 2008; accepted 10 March 2008; online 14 March 2008)

The title compound, C₁₆H₂₂N₄P₂, crystallizes about a centre of symmetry, leading to a chair conformation of the heterocyclic ring as is commonly found for this type of compound.

Related literature

For related structures, see: Reddy et al. (1994 , 1995 ).

Experimental

Crystal data

C₁₆H₂₂N₄P₂
M_r = 332.32
Orthorhombic, P b c a
a = 13.2879 (16) Å
b = 7.5426 (9) Å
c = 17.125 (2) Å
V = 1716.4 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.26 mm⁻¹
T = 173 (2) K
0.38 × 0.27 × 0.26 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: none
10040 measured reflections
1873 independent reflections
1591 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.030
wR(F²) = 0.094
S = 1.08
1873 reflections
100 parameters
H-atom parameters constrained
Δρ_max = 0.32 e Å⁻³
Δρ_min = −0.25 e Å⁻³

Data collection: SMART-NT (Bruker, 1998 ); cell refinement: SAINT-Plus (Bruker, 1999 ); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053680800665X/tk2250sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680800665X/tk2250Isup2.hkl

checkCIF report

Comment top

Compound (I) has a centre of symmetry and the six-membered ring adopts a chair conformation with the phenyl groups on the phosphorous atoms being trans to each other. Reddy et al. (1994) have observed in related compounds, e.g. [HNP(Et)N(Me)]₂ and [HNP(Ph)N(Me)]₂, that the chair conformation was favoured over the boat conformation and was seen to readily crystallize. Bond lengths and angles in (I), with values for N—N 1.4321 (17), P—N 1.6953 (14) and 1.6984 (12), and P—C_arom 1.8412 (15) Å, are in the ranges observed in related structures (Reddy et al., 1994, 1995).

Related literature top

For related structures, see: Reddy et al. (1994, 1995).

Experimental top

In an attempt to crystallize bis(diphenylphosphino)dimethylhydrazine (II) (for synthesis see Reddy et al., 1995), the worked-up diethylether reaction mixture was concentrated and kept at -20 °C for two days. Two small crystals were formed and on analysis of one of the crystals, (I) was identified. Analysis of the ³¹P NMR spectrum of (II) showed (I) to be present in less than 5%. Further analysis of (I) was not attempted due to the small amount of material available.

Computing details top

Data collection: SMART-NT (Bruker, 1998); cell refinement: SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

Fig. 1. Molecular structure of (I) drawn with displacement ellipsoids at the 50% probability level. Hydrogen atoms have been omitted for clarity.

1,2,4,5-Tetramethyl-3,6-diphenyl-1,2,4,5-tetraaza-3,6-diphosphinane top

Crystal data top

C₁₆H₂₂N₄P₂	F(000) = 704
M_r = 332.32	D_x = 1.286 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 899 reflections
a = 13.2879 (16) Å	θ = 3.0–28.2°
b = 7.5426 (9) Å	µ = 0.26 mm⁻¹
c = 17.125 (2) Å	T = 173 K
V = 1716.4 (4) Å³	Plates, colourless
Z = 4	0.38 × 0.27 × 0.26 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	1591 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.031
Graphite monochromator	θ_max = 27.0°, θ_min = 2.4°
ϕ and ω scans	h = −15→16
10040 measured reflections	k = −7→9
1873 independent reflections	l = −21→21

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.030	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.094	H-atom parameters constrained
S = 1.08	w = 1/[σ²(F_o²) + (0.0506P)² + 0.5379P] where P = (F_o² + 2F_c²)/3
1873 reflections	(Δ/σ)_max = 0.005
100 parameters	Δρ_max = 0.32 e Å⁻³
0 restraints	Δρ_min = −0.25 e Å⁻³

Crystal data top

C₁₆H₂₂N₄P₂	V = 1716.4 (4) Å³
M_r = 332.32	Z = 4
Orthorhombic, Pbca	Mo Kα radiation
a = 13.2879 (16) Å	µ = 0.26 mm⁻¹
b = 7.5426 (9) Å	T = 173 K
c = 17.125 (2) Å	0.38 × 0.27 × 0.26 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	1591 reflections with I > 2σ(I)
10040 measured reflections	R_int = 0.031
1873 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.030	0 restraints
wR(F²) = 0.094	H-atom parameters constrained
S = 1.08	Δρ_max = 0.32 e Å⁻³
1873 reflections	Δρ_min = −0.25 e Å⁻³
100 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C1	−0.08579 (13)	0.3217 (2)	−0.05297 (9)	0.0359 (4)
H1A	−0.0364	0.4122	−0.0624	0.054*
H1B	−0.1442	0.3737	−0.0292	0.054*
H1C	−0.1044	0.2675	−0.1016	0.054*
C2	0.17104 (11)	−0.0731 (2)	−0.08775 (8)	0.0336 (3)
H2A	0.2138	0.0277	−0.0961	0.050*
H2B	0.1272	−0.0878	−0.1319	0.050*
H2C	0.2116	−0.1775	−0.0815	0.050*
C11	0.09375 (10)	0.14618 (18)	0.11718 (8)	0.0257 (3)
C12	0.03662 (11)	0.25669 (19)	0.16564 (8)	0.0295 (3)
H12	−0.0127	0.3288	0.1438	0.035*
C13	0.05251 (13)	0.2604 (2)	0.24603 (9)	0.0339 (3)
H13	0.0135	0.3338	0.2775	0.041*
C14	0.12622 (12)	0.1549 (2)	0.27919 (9)	0.0362 (4)
H14	0.1359	0.1554	0.3330	0.043*
C15	0.18563 (12)	0.0482 (2)	0.23183 (9)	0.0372 (4)
H15	0.2359	−0.0215	0.2539	0.045*
C16	0.17020 (11)	0.0452 (2)	0.15125 (9)	0.0307 (3)
H16	0.2112	−0.0248	0.1199	0.037*
N1	−0.04376 (10)	0.18785 (15)	−0.00091 (7)	0.0277 (3)
N2	0.11088 (9)	−0.04525 (16)	−0.01743 (7)	0.0277 (3)
P1	0.08233 (3)	0.16498 (5)	0.01035 (2)	0.02618 (14)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0509 (10)	0.0263 (8)	0.0304 (8)	0.0060 (7)	−0.0051 (7)	0.0052 (6)
C2	0.0319 (7)	0.0386 (8)	0.0302 (7)	0.0019 (6)	0.0104 (6)	−0.0022 (6)
C11	0.0285 (7)	0.0237 (7)	0.0250 (7)	−0.0039 (5)	0.0019 (5)	0.0006 (5)
C12	0.0330 (7)	0.0262 (7)	0.0292 (7)	0.0013 (6)	0.0007 (6)	0.0004 (6)
C13	0.0375 (8)	0.0345 (8)	0.0298 (8)	−0.0014 (6)	0.0017 (6)	−0.0076 (7)
C14	0.0391 (9)	0.0413 (9)	0.0283 (7)	−0.0057 (7)	−0.0076 (6)	−0.0036 (6)
C15	0.0339 (8)	0.0385 (9)	0.0392 (8)	0.0016 (7)	−0.0129 (6)	−0.0017 (7)
C16	0.0269 (7)	0.0306 (7)	0.0346 (7)	−0.0002 (6)	−0.0009 (6)	−0.0042 (6)
N1	0.0323 (6)	0.0226 (6)	0.0282 (6)	0.0037 (5)	0.0036 (5)	0.0076 (5)
N2	0.0314 (6)	0.0252 (6)	0.0265 (6)	0.0025 (5)	0.0099 (5)	0.0015 (5)
P1	0.0307 (2)	0.0230 (2)	0.0248 (2)	0.00033 (14)	0.00652 (14)	0.00337 (13)

Geometric parameters (Å, º) top

C1—N1	1.4583 (18)	C12—H12	0.9300
C1—H1A	0.9600	C13—C14	1.384 (2)
C1—H1B	0.9600	C13—H13	0.9300
C1—H1C	0.9600	C14—C15	1.389 (2)
C2—N2	1.4605 (17)	C14—H14	0.9300
C2—H2A	0.9600	C15—C16	1.395 (2)
C2—H2B	0.9600	C15—H15	0.9300
C2—H2C	0.9600	C16—H16	0.9300
C11—C16	1.398 (2)	N1—N2ⁱ	1.4321 (17)
C11—C12	1.400 (2)	N1—P1	1.6953 (14)
C11—P1	1.8412 (15)	N2—N1ⁱ	1.4321 (17)
C12—C13	1.393 (2)	N2—P1	1.6984 (12)

N1—C1—H1A	109.5	C12—C13—H13	120.0
N1—C1—H1B	109.5	C13—C14—C15	119.73 (14)
H1A—C1—H1B	109.5	C13—C14—H14	120.1
N1—C1—H1C	109.5	C15—C14—H14	120.1
H1A—C1—H1C	109.5	C14—C15—C16	120.24 (14)
H1B—C1—H1C	109.5	C14—C15—H15	119.9
N2—C2—H2A	109.5	C16—C15—H15	119.9
N2—C2—H2B	109.5	C15—C16—C11	120.72 (14)
H2A—C2—H2B	109.5	C15—C16—H16	119.6
N2—C2—H2C	109.5	C11—C16—H16	119.6
H2A—C2—H2C	109.5	N2ⁱ—N1—C1	114.56 (12)
H2B—C2—H2C	109.5	N2ⁱ—N1—P1	120.94 (9)
C16—C11—C12	118.12 (13)	C1—N1—P1	121.23 (10)
C16—C11—P1	121.12 (11)	N1ⁱ—N2—C2	114.43 (11)
C12—C11—P1	119.90 (11)	N1ⁱ—N2—P1	120.04 (9)
C13—C12—C11	121.04 (14)	C2—N2—P1	119.18 (10)
C13—C12—H12	119.5	N1—P1—N2	106.49 (6)
C11—C12—H12	119.5	N1—P1—C11	101.67 (6)
C14—C13—C12	120.08 (14)	N2—P1—C11	100.84 (6)
C14—C13—H13	120.0

C16—C11—C12—C13	−2.7 (2)	N2ⁱ—N1—P1—C11	−66.99 (11)
P1—C11—C12—C13	−172.18 (11)	C1—N1—P1—C11	134.55 (11)
C11—C12—C13—C14	0.5 (2)	N1ⁱ—N2—P1—N1	−37.75 (13)
C12—C13—C14—C15	1.3 (2)	C2—N2—P1—N1	112.73 (11)
C13—C14—C15—C16	−1.0 (2)	N1ⁱ—N2—P1—C11	68.00 (11)
C14—C15—C16—C11	−1.3 (2)	C2—N2—P1—C11	−141.52 (11)
C12—C11—C16—C15	3.1 (2)	C16—C11—P1—N1	148.76 (12)
P1—C11—C16—C15	172.42 (12)	C12—C11—P1—N1	−42.10 (12)
N2ⁱ—N1—P1—N2	38.17 (13)	C16—C11—P1—N2	39.20 (13)
C1—N1—P1—N2	−120.30 (12)	C12—C11—P1—N2	−151.65 (11)

Symmetry code: (i) −x, −y, −z.

Experimental details

Crystal data
Chemical formula	C₁₆H₂₂N₄P₂
M_r	332.32
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	173
a, b, c (Å)	13.2879 (16), 7.5426 (9), 17.125 (2)
V (Å³)	1716.4 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.26
Crystal size (mm)	0.38 × 0.27 × 0.26

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	10040, 1873, 1591
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.030, 0.094, 1.08
No. of reflections	1873
No. of parameters	100
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.32, −0.25

Computer programs: SMART-NT (Bruker, 1998), SAINT-Plus (Bruker, 1999), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006), WinGX (Farrugia, 1999).

Acknowledgements

The authors thank Project AuTEK (Mintek and Harmony Gold) and the University of the Witwatersrand for financial support.

References

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